Q: Over this period of time, do you think human activity had a mostly (positive) or mostly (negative) effect on the natural environment? Is that a very positive/negative effect or a somewhat positive/negative effect?

In this poll:

On the eve of a major international gathering aimed at forging a new road map for sustainable development, a Washington Post poll shows that most Americans think the world's natural environment has deteriorated over the past decade.

This Washington Post poll was conducted by telephone June 14 to 17, 2012, among a random national sample of 1,002 adults, including users of both conventional and cellular phones. Results for the full sample have a 3.5 point error margin. Sampling, data collection and tabulation by PSRAI of Princeton, New Jersey.